\version "2.7.39"
\header
{
  texidoc = "The multimeasure rest is centered exactly between bar lines."

}

\layout { ragged-right = ##t}




{
  \set Score.skipBars = ##t
  \override Staff.BarLine  #'hair-thickness = #7.5
  \override Staff.MultiMeasureRest  #'hair-thickness = #10

  c'1 R1*20 c'1
}